This invention relates generally to air conditioning, and more particularly to air conditioning units of the split system type in which the compressor and condenser elements are mounted remotely from the evaporator element, usually in an exterior location.
Air conditioning units for homes and other small buildings have usually been of two types. One type is the unitary room air conditioning unit in which the compressor, condenser and evaporator and necessary fans are mounted in a single unit which is placed either in a window opening or in a separate through-the-wall mounting so that the evaporator units can be used to cool the air inside the building while the condenser is mounted on the outside portion of the unit to discharge the heat into the atmosphere. The other type is the split system in which the evaporator is mounted inside the building, while the compressor and condenser units are then mounted outside at a suitable location. In the case of the split system, the only connection between the units need be the two refrigerant lines and the necessary electrical and control connections for the system. Generally, the unitary room air conditioner units are of smaller size than the split system units and, because of the relatively high capacity of the latter, the condenser unit requires special consideration with regard to noise reduction and air flow because of the larger capacity.
Recently, however, it has been proposed to make relatively small split system units which may be used for cooling only a single room with a single evaporator unit having a size similar to that used in unitary room air conditioners. While the small split system is of greater cost than a room air conditioner unit, it does offer a number of advantages, such as not requiring a window or other large opening for mounting the unit, since the evaporator can be placed against a bare wall and only a relatively small opening through the wall is required for the refrigerant and electrical connections. Furthermore, such a unit, by allowing remote placement of the compressor, condenser and condenser fan, allows a substantial reduction of noise in the room while still providing sufficiently high cooling capacity for relatively large rooms in hot climates. However, such units are still of generally smaller size than central system air conditioners, and do not require the amount of sound muffling and special air flow considerations required for the condenser units of that type.